Significance of spontaneous apoptosis during colorectal tumorigenesis

To determine if apoptosis is involved in colorectal tumorigenesis and its progression, colorectal adenomas (n = 63), carcinomas (n = 49), and normal mucosa were investigated by using in situ end-labeling (TUNEL) method. The expression of Ki-67 was also analyzed immunohistochemically. TUNEL labeling index (TLI) and Ki-67 labeling index (KLI) were determined. TLI/KLI was significantly higher in the adenomas of small size and/or of low and middle grade atypia than those of large size and/or of high grade atypia. No difference was observed in the indices between adenomas and carcinomas and among the cancer groups classified on the basis of their clinicopathological features. The results indicate that the reduction of susceptibility to apoptosis plays an important role in the early stage of the adenoma-carcinoma sequence. Apoptosis can explain the enormous cell loss thought to exist in normal colorectal mucosa and in the tumor growth process. © 1996 Wiley-Liss, Inc.     

Survivin在结直肠癌组织中表达的临床意义及其与细胞凋亡、血管生成的关系

背景与目的:关于survivin在结直肠癌中的表达及其与病理因素、细胞凋亡及血管生成的关系仍然不清楚。本研究旨在通过探讨survivin在结直肠癌中的表达对细胞凋亡的影响及其与血管生成的关系,以认识survivin对结直肠癌发展及预后的影响。方法:应用免疫组化技术检测survivin、血管内皮生长因子(vascular endothelial growth factor.VEGF)在91例结直肠癌组织中的蛋白表达,TUNEL法检测癌细胞凋亡指数(apoptosis index,AI)。结果:结直肠癌伴远处器官转移者的survivin蛋白表达(56%,14/25)高于未转移者(48.5%,32/66)(P<0.05),5年生存者survivin蛋白表达阳性率穴(n阳性患者平均生存期为91.3月熏阴性患者为116.4月,前者的5年生存率穴65.2%熏30/46雪显著低于survivin阴性者穴88.9%熏40/45雪穴P<0.01雪;survivin阳性患者的AI均数(0.74±0.19)%显著低于阴性患者(1.07±0.24)%穴P<0.01雪;survivin与VEGF蛋白表达显著相关穴Pearson系数:0.721雪。结论:survivin可抑制结直肠癌细胞凋亡和调节肿瘤血管生成。     

Neuritin expression and its relation with proliferation, apoptosis, and angiogenesis in human astrocytoma

Neuritin, a new member of the neurotrophic factor family, plays an important role in promoting neuronal survival, differentiation, function, and repair. However, whether neuritin is expressed in human astrocytoma and involved in their proliferation, apoptosis, and angiogenesis remains unclear. The expression of neuritin messenger RNA, protein and the relationship with proliferation, apoptosis, and angiogenesis were examined in human astrocytoma samples and three glioma cell lines by immunohistochemistry, Western blot, and quantitative real-time RT–PCR and so on. And neuritin immunoreactivity score(IRS), proliferative index (PI), apoptotic index (AI), overall daily growth (ODG), and microvessel density (MVD) in brain astrocytoma were measured. The results showed that neuritin was overexpressed in human astrocytoma samples, and the overexpression correlated positively with the malignancy of astrocytomas as reflected by changes in proliferation, apoptosis, and angiogenesis markers. In our study, we found neuritin is overexpressed in astrocytoma, which may be an important factor in tumorigenesis and progression of astrocytoma, and can be used as a target for biological therapy.     

Ｓｕｒｖｉｖｉｎ在喉鳞癌中的表达及其与肿瘤细胞增殖和凋亡的关系*

目的　分析Ｓｕｒｖｉｖｉｎ在喉鳞癌中的表达及其与肿瘤细胞增殖、凋亡的关系,并探讨其与喉鳞癌临床病理特征之间的关系。方法　应用免疫组化染色技术检测Ｓｕｒｖｉｖｉｎ和Ｋｉ-６７在８６例喉鳞癌组织及３２例正常喉黏膜上皮组织中的表达;ＴＵＮＥＬ法检测喉鳞癌细胞的凋亡情况。结果　Ｓｕｒｖｉｖｉｎ在喉鳞癌组织中阳性表达率为６０.５％,高于正常喉黏膜上皮组织的１２.５％（Ｐ＜０.０５）,Ｓｕｒｖｉｖｉｎ阳性表达率与肿瘤临床分期、病理分级、淋巴结转移有关（Ｐ＜０.０５）;喉鳞癌Ｓｕｒｖｉｖｉｎ阳性组中凋亡指数（ＡＩ）低于阴性组（Ｐ＜０.０５）,增殖指数（ＰＩ）高于阴性组（Ｐ＜０.０５）,且Ｓｕｒｖｉｖｉｎ表达与ＡＩ呈负相关（ｒ＝－０.８３１,Ｐ＜０.０５）,与ＰＩ呈正相关（ｒ＝０.８８３,Ｐ＜０.０５）。结论　Ｓｕｒｖｉｖｉｎ在喉鳞癌中高表达,可能与喉鳞癌细胞的增殖和凋亡均有一定的关联。     

The survivin -31 snp in human colorectal cancer correlates with survivin splice variant expression and improved overall survival

Background

Survivin is involved in the regulation of cell division and survival, two key processes in cancer. The majority of studies on survivin in colorectal cancer (CRC) have focused on protein expression and less is known about the expression of survivin splicing variants or survivin gene polymorphisms in CRC. In the present study, the mRNA levels of the five known isoforms of survivin as well as survivin protein were assessed in matched normal and neoplastic colorectal tissue. Moreover, the 9386 C/T and -31 G/C polymorphisms were investigated.

Methods

Quantitative RT-PCR was used to assess mRNA levels in fresh/frozen tissue samples. Protein levels were immunohistochemically evaluated on formalin-fixed paraffin-embedded tissue sections. Individuals were genotyped using real time PCR

Results

Expression of all 5 survivin splice variants as well as survivin protein was elevated in colorectal carcinomas compared to normal tissue. Specific splice variant expression differentially correlated with clinicopathological parameters. Furthermore, both snps correlated with splice variant levels or their ratios in colorectal carcinomas while the -31 G/C snp may be related to CRC development and improved overall survival.

Conclusion

Our results support a role of survivin in colorectal carcinogenesis while the -31 G/C snp may constitute a marker of survival.     

Triplex-forming oligodeoxynucleotides targeting survivin inhibit proliferation and induce apoptosis of human lung carcinoma cells

Survivin is expressed in most cancers but is undetectable in differentiated adult cells, and plays an important role both in the suppression of apoptosis and mitotic spindle checkpoint; thus it has attracted great interest as a potential drug target. In this study, we investigated the antigene and antiproliferative effects of triplex-forming oligodeoxynucleotides (TFO) targeting survivin in human lung carcinoma A549 cells. Survivin-specific TFOs form stable triplexes under physiological conditions as tested by electrophoretic mobility shift assays. Treatment of A549 cells with survivin-specific but not control TFOs at a concentration of 400 nM in the presence of uptake-enhancing liposome significantly reduced survivin protein level, inhibited cell proliferation, and induced cell apoptosis as demonstrated by immunoblot, cell number counting, and Annexin V-staining. Moreover, we found that the triplex-forming potential of TFOs measured in vitro does not necessarily correlate with the ability of TFOs to affect expression of a targeted gene in vivo. Our results indicate that targeting survivin is a promising alternative strategy for the development of novel anticancer therapeutics.     

Calpain 6 supports tumorigenesis by inhibiting apoptosis and facilitating angiogenesis

Since calpain 6 is overexpressed in uterine cervical cancer tissue compared to normal tissue, we sought to define the role of calpain 6 during tumorigenesis. We overexpressed calpain 6 or inhibited calpain 6 in human cervical cancer cells (HeLa cells) and human umbilical vein endothelial cells (HUVECs), and measured cisplatin-mediated apoptosis and VEGF-mediated angiogenesis. The results indicated that calpain 6 supported tumorigenesis by inhibiting apoptosis and facilitating angiogenesis. To our knowledge, this result is the first evidence implicating calpain 6 in tumorigenesis, and it reveals calpain 6 as a novel therapeutic target for certain types of cancers.     

Ciprofloxacin induces apoptosis and inhibits proliferation of human colorectal carcinoma cells

Efficacy of chemotherapy in advanced stages of colorectal tumours is limited. The quinolone antibiotic ciprofloxacin was recently shown to inhibit growth and to induce apoptosis in human bladder carcinomas cells. We investigated the effect of ciprofloxacin on colon carcinoma lines in vitro. CC-531, SW-403 and HT-29 colon carcinoma and HepG2 hepatoma cells (control cells) were exposed to ciprofloxacin. Proliferation was assessed by bromodeoxyuridine-incorporation into DNA and apoptosis was measured by flow cytometry after propidium iodide or JC-1 staining. Expression of anti-apoptotic Bcl-2 and pro-apoptotic Bax was analyzed by semiquantitative Western blot analysis and activity of caspases 3, 8 and 9 by substrate-cleavage assays. Ciprofloxacin suppressed DNA synthesis of all colon carcinoma cells time- and dose-dependently, whereas the hepatoma cells remained unaffected. Apoptosis reached its maximum between 200 and 500 microg ml(-1). This was accompanied by an upregulation of Bax and of the activity of caspases 3, 8 and 9, and paralleled by a decrease of the mitochondrial membrane potential. Ciprofloxacin decreases proliferation and induces apoptosis of colon carcinoma cells, possibly in part by blocking mitochondrial DNA synthesis. Therefore, qualification of ciprofloxacin as adjunctive agent for colorectal cancer should be evaluated.     

Ｓｕｒｖｉｖｉｎ和Ｃａｓｐａｓｅ-３在脑胶质瘤中的表达及其与细胞凋亡的关系

目的：探讨Ｓｕｒｖｉｖｉｎ和Ｃａｓｐａｓｅ-３在脑胶质瘤中的表达及其意义。方法：采用免疫组化法、原位杂交法分别检测６８例脑胶质瘤和１０例内减压脑组织中Ｓｕｒｖｉｖｉｎ、Ｃａｓｐａｓｅ-３蛋白及其ｍＲＮＡ的表达情况;原位末端标记法（ＴＵＮＥＬ）法检测胶质瘤细胞凋亡情况。结果：Ｓｕｒｖｉｖｉｎ蛋白及其ｍＲＮＡ在脑组织与胶质瘤中的阳性表达率有显著差异,两者在脑胶质瘤Ⅲ、Ⅳ级组织中的表达明显高于Ⅰ、Ⅱ级;Ｃａｓｐａｓｅ-３蛋白及其ｍＲＮＡ在脑组织与胶质瘤中阳性表达率均无显著差异。脑胶质瘤组织中Ｓｕｒｖｉｖｉｎ和Ｃａｓｐａｓｅ-３的表达呈负相关。脑胶质瘤组织细胞的凋亡指数（ＡＩ）范围是７％ ～２９％,平均（１６５９±６１９）％;Ｓｕｒｖｉｖｉｎ阳性组的ＡＩ值明显小于阴性组（Ｐ＜０.０５）;Ｃａｓｐａｓｅ-３阳性组的ＡＩ值明显大于阴性组（Ｐ＜０.０５）。结论：Ｓｕｒｖｉｖｉｎ与凋亡途径的关键因子Ｃａｓｐａｓｅ-３关系密切,若把Ｓｕｒｖｉｖｉｎ作为靶点来阻断抗凋亡途径,促进肿瘤细胞凋亡,将会是很好的抗肿瘤策略。     

Survivin expression and its relation with proliferation, apoptosis, and angiogenesis in brain gliomas

BACKGROUND: An unbalance of cell proliferation and cell apoptosis is an important mechanism in carcinogenesis, and angiogenesis also plays a crucial role in tumorigenesis. Recently, survivin has been identified as an important member of the inhibitor of apoptosis protein (IAP) family. Although it has been shown that survivin is highly expressed in gliomas, and is associated with tumorigenesis, progression, and poor prognosis of gliomas, as yet the relation of survivin expression with proliferation, apoptosis, and angiogenesis of gliomas it is still unclear. METHODS: Eighty-three cases of brain glioma were chosen and protein expressions of survivin and proliferating cell nuclear antigen (PCNA) in glioma cells and Factor VIII-related antigen (FVIII-RAg) in vascular endothelial cells were investigated by immunohistochemistry. Apoptotic cells of brain glioma were screened by TdT-mediated dUTP nick end-labeling (TUNEL), and survivin immunoreactivity score (IRS), proliferative index (PI), apoptotic index (AI), overall daily growth (ODG), and microvessel density (MVD) in brain gliomas were measured. RESULTS: The survivin IRS, PI, AI, ODG, and MVD of brain gliomas were 3.75 +/- 3.89, 28.39 +/- 19.49%, 1.00 +/- 0.80%, 12.19 +/- 10.21%, and 62.75 +/- 31.50, respectively, and all of them increased markedly with an increase in the pathologic grade of brain gliomas (P < 0.001 for all). PI, ODG, and MVD in the survivin-positive group were significantly higher than those in the survivin-negative group (P < 0.001 for all). PI, ODG, and MVD were positively correlated with survivin IRS (P < 0.001 for all). Although there was no significant difference between AI in the survivin-positive group or in the survivin-negative group (P = 0.108), AI was inversely correlated with survivin IRS (P = 0.005). CONCLUSIONS: Survivin is overexpressed in brain gliomas, which may play an important role in malignant proliferation, antiapoptosis, and angiogenesis of brain gliomas.     

术前区域动脉灌注生长抑素和化疗药物对结肠癌细胞增殖、凋亡和血管形成的影响

目的探讨术前区域动脉灌注生长抑素和化疗药物对细胞增殖、凋亡和血管形成的影响。方法结肠癌病人45例,随机分为A、B和C组,每组15例。A组为术前加入善宁的区域动脉灌注化疗组,B组为术前不加入善宁的区域动脉灌注化疗组,C组不采用区域动脉灌注化疗常规手术组。切除标本行MVD、VEGF、Ki67LI、ALI检察。结果A、B、C组MVD分别为12±8、25±17、26±16(P<0.05),VEGF表达分别为39、70、72,Ki67LI分别为8±4、11±6、16±7(P<0.05),ALI分别为4.3±0.5、2.2±0.6、1.5±0.6(P<0.05)。区域动脉灌注化疗对肿瘤增殖有抑制作用,并促进细胞凋亡,加入善宁可以加强上述作用外,对肿瘤血管形成具有抑制作用。结论术前区域动脉灌注化疗药物,可以提高结肠癌的疗效,生长抑素可以增强其抗肿瘤作用。     

Increased expression of RelA/nuclear factor-kappa B protein correlates with colorectal tumorigenesis

OBJECTIVE: To identify the role of RelA/nuclear factor-kappa B, an important inhibitor of apoptosis in colorectal tumorigenesis, we examined the expression of RelA in normal colorectal mucosa (n = 10), colorectal adenomas (n = 30) and colorectal adenocarcinomas (n = 30). Furthermore, the association of RelA expression with tumor cell apoptosis, proliferation, and expression of Bcl-2/Bcl-x(L )was also studied. METHODS: Paraffin sections were stained with monoclonal antibodies directed against RelA, Bcl-2, Bcl-x(L), and Ki-67 to assess protein expression patterns in normal, adenomatous and colon cancer tissue. Apoptotic cells were detected by terminal deoxynucleotidyl-transferase-mediated dUTP-biotin nick end labeling (TUNEL) using an in situ detection kit. RESULTS: The results of immunohistochemical staining revealed that expression of RelA, Bcl-2, Bcl-x(L), and Ki-67 labeling index (LI) significantly increased in the transition from adenoma with low dysplasia to adenocarcinoma. This transition was associated with a significant decrease in the apoptotic index (AI) and a significant increase in the Ki-67 LI. The expression of RelA correlated inversely with the AI and correlated positively with the expression of Bcl-2, Bcl-x(L), and Ki-67 LI in the transition from low-grade dysplasia to adenocarcinoma. CONCLUSION: Our results suggest that increased expression of RelA/nuclear factor-kappa B plays an important role in the transition from colorectal adenoma with low-grade dysplasia to adenocarcinoma in the pathogenesis of colon cancer in humans.     

The human tumor suppressor CEACAM1 modulates apoptosis and is implicated in early colorectal tumorigenesis

Defects in the adenomatous polyposis coli (APC) tumor suppressor pathway are sufficient for neoplastic transformation as the initiating step in colorectal carcinogenesis. In contrast, hyperplastic tumors possess normal APC function, and it is unclear whether they represent significant precursor lesion in cancer development. CEACAM1 is a tumor suppressor whose expression is known to be lost in the great majority of early adenomas and carcinomas. We found that loss of CEACAM1 expression is more common in neoplastic tumors than APC mutations. While APC function was normal in hyperplastic aberrant cypt foci and hyperplastic polyps, loss of CEACAM1 was observed as frequently as in the neoplasias. Moreover, the presence or absence of CEACAM1 expression in the hyperplastic tumors correlates with normal or reduced apoptosis, respectively. In vitro, CEACAM1 acts as a regulator of apoptosis in CEACAM1-transfected Jurkat cells. Finally, in human HT29 colon cancer cells, apoptosis can be specifically restored by induction of CEACAM1 expression. These data suggest an oncodevelopmental link between neoplasia and hyperplasia and demonstrate that CEACAM1 acts as a regulator of apoptosis in the colonic epithelium. Thus, failure of the maturing colon cell to express CEACAM1 is likely to contribute to the development of hyperplastic lesions, which may eventually pave the way to neoplastic transformation and colon cancer development.     

Survivin在结直肠癌中的表达及其临床意义

目的:探讨结直肠癌组织中凋亡抑制因子Survivin的表达及其与各临床病理因素的关系,评价Survivin在结直肠癌预后判断中的价值。方法:应用组织芯片结合免疫组织化学SABC法,检测126例结直肠癌组织中Survivin的表达情况,分析Survivin与各临床病理因素及预后之间的关系。结果:根据免疫组化染色强度和分级结果,所有病例被分为Survivin高表达组和低表达组。其中高表达组有26例(26/126,20·6%),低表达组有100例(100/126,79·4%)。Survivin在结直肠癌中表达情况与年龄、性别、肿瘤大小、肿瘤部位、组织学类型、浸润深度、淋巴是否转移和Dukes分期均无显著相关。然而,高表达的Survivin与肿瘤复发、特别是血行转移显著相关,P<0·05。Survivin高表达组和低表达组的生存率用Kaplan-Meier方法评估,并用log-rank test进行比较,两组之间生存率差异具有统计学意义,P<0·05。多因素分析结果显示,在潜在的预后因素中(年龄、性别、肿瘤大小、肿瘤部位、组织学类型、淋巴是否转移和Dukes分期、Survivin表达),Survivin表达和Dukes分期被认为是结直肠癌根治术后独立预后因素。结论:Survivin的表达与结直肠癌的术后复发相关:结直肠癌术后复发率在Survivin高表达组明显高于Survivin低表达组,是与预后相关的独立危险因子。应用组织芯片高效检测临床组织样本具有快速、方便、经济、准确的优点。